Sheet feeding from a selectable one of media supplies into a transport path

Abstract: A method and apparatus automatically switches from one web media type to another, using a single drive roller (36) to access and drive one of two web media supply cassettes (16) mounted within an imaging system. A gear motor (45) and eccentric shaft (46) position and load the drive roller (36) against either of two driven rollers (32, 34). The media is nipped between the drive roller (36) and one of the driven rollers (34) and is advanced by the drive roller (36) into the imaging system as needed. To switch media supply cassettes, the media is cut beyond the drive roller. The media is then drawn back into the supply cassette (16) to free the media path (24) for the alternate media to advance from the other of the two media supply cassettes.

Description: The invention is intended to answer a long-felt need in the field of image recording. More specifically, the invention allows for selection of a media type, whether it be paper, film, or plate, or a different size media of the same type. Two media supply cassettes are mounted within an internal drum recorder, or the like. Selection of the media can be programmed to be automatic, or can be input by a user's command. Apparatuses capable of selecting from among plural media are e.g. disclosed in US-A-4 868 674, US-A-4 980 717, and DE-A-4 022 883. A general object of the invention is to select media from one of two supply cassettes that are mounted within an imaging system, by an alternative arrangement compared to the prior art. It is a further general object of the invention to prevent waste of unexposed media. The invention is as defined in the appended claims. Generally, the invention involves an apparatus for selecting one of two media supply cassettes to feed media into a media path comprises input means for inputting a command designating a selected supply cassette and positioning means for automatically positioning a drive roller into a position corresponding to the command. The drive roller contacts a driven roller adjacent to the selected supply cassette and pinches a leading edge of media therebetween that extends out from the selected supply cassette into a feed path of the selected supply cassette. The apparatus also includes driving means for driving the drive roller to feed the media out from the selected supply cassette through the feed path and into the media path. A feature of the invention is a rewinding mechanism provided on the media supply cassettes. A corresponding method for selecting media from one of two media supply cassettes to feed the media into a media path comprises inputting a command to designate a selected supply cassette and automatically positioning a drive roller into a position corresponding to the command. The drive roller contacts a driven roller adjacent to the selected supply cassette, and pinches a leading edge of media therebetween that extends out from the selected supply cassette into a feed path of the selected supply cassette. The next step is driving the drive roller to feed the media out from the selected supply cassette through the feed path and into the media path. The features and objects of the invention will become apparent in the following description when taken with the accompanying drawings, in which: Figure 1 is a side view of an input media selector. Figure 2 is sectional view of a roller drive assembly used in the input media selector. Figure 3 is a view similar to Figure 2 including more details of the roller drive assembly. Referring to Fig. 1, two mounting brackets (8, 10) are provided in a housing (14) of an imaging system for supporting two media supply cassettes (16) (one shown). There are two media feed paths (18, 20) that begin at each supply cassette (16) and join to form a main media path (24) downstream of a roller drive assembly, generally referred to by reference numeral (30). The drive roller assembly (30), has two driven rollers (32, 34) that are located in fixed positions adjacent to the media feed paths (18, 20), respectively. A drive roller (36) is positioned between the two driven rollers (32, 34) and is movable to be in rolling contact with either of the driven rollers (32, 34). The drive roller (36) is rotatably mounted on a movable bracket (38). Referring now to Figs. 1 and 2, the movable bracket (38) carries a drive motor (39) that has a motor gear (40) engaged with a drive roller gear (41) nonrotatably mounted to the end of the drive roller (36). Upon rotation of the drive motor (39), the motor gear (40) rotates drive roller gear (41), which in turn rotates the drive roller (36). The driven rollers (32, 34) each have a gear (42) (tooth profile partially shown), (43), mounted nonrotatably to an end respectively, that is either partially or fully engaged with drive roller gear (41). In Fig. 2 it can be seen that gears (41) and (42) are fully engaged and gears (41) and (43) are partially engaged. The drive roller gear (41) drives both of the driven roller gears (42, 43) when rotated to avoid misalignment problems that might occur if the gears were to completely disengage. However, the drive roller (36) contacts only one of the driven rollers (32, 34) at a time due to a clearance provided between the drive roller (36) and the driven rollers (32, 34). In Fig. 2, drive roller (36) and driven roller (32) advance the media from media feed path (18) while the clearance allows the leading edge (44) of the non-selected media supply cassette to extend between and beyond the drive roller (36) and the driven roller (34) without advancing, despite rotation of the drive roller (36) and the driven roller (34). A gear motor (45) (Fig. 1) has an eccentric shaft (46) and is rigidly mounted to the housing (14). Referring now to Figs. 1 and 3, the eccentric shaft (46) passes through an aperture (48) in a bracket (50) that is attached to the movable bracket (38) by a pivotable fastener (52). A rectangular bronze bushing (54) is located between the bracket (50) and the eccentric shaft (46). Two compression springs (56) apply a predetermined load to the bronze bushing (54) by means of set screws (57). When driven by the eccentric shaft (46), the bracket (50) moves linearly toward the bracket (38) causing the bracket (38) to pivot at pivot points (52) and (58). Since the drive roller is mounted to bracket (38), it pivots back and forth between the two driven rollers (32) and (34). To select media from one of the two supply cassettes, the user of the imaging system inputs a command indicating the desired supply cassette. Through control software and hardware (not shown) the gear motor (45) is activated to drive the eccentric shaft (46). The rotary motion of the eccentric shaft (46) is translated through the aperture (48) into pivotal motion of the bracket (38) about pivot point (58). If the lower supply cassette (16) is selected, the eccentric shaft (46) drives the bracket (50) to the right, causing bracket (38) and drive roller (36) to pivot with respect to pivot point (58) (Fig. 3) in a clockwise direction toward the driven roller (34). A leading edge of media extending out of supply cassette (16) into the feed path (20) is nipped between the rollers (34), (36) as the drive roller is pressed against the driven roller (34). Then, the eccentric shaft (46) is driven further, causing the bushing (54) to compress the spring (56) to the right of the aperture (48) and thus move the brackets (50), (38) to provide a firm force between the drive roller (36) and the driven roller (34). A flag (60) (Fig. 1) mounted on the bracket (38) breaks a beam of light within a photo interrupter (62) which is mounted to the housing (14). The flag (60) breaks the beam of light when the drive roller (36) has reached the proper position against driven roller (34), and the gear motor (45) is switched off. Next, the drive roller motor (39) is switched on thereby driving drive roller (36) in a clockwise direction. The media that has been nipped between the drive roller (36) and the driven roller (34) is advanced through the feed path (20) and into the main media path (24) as needed. A jam sensor (70) is shown in Fig. 1 at the entrance to the media path (24). The jam sensor (70) senses the motion of the media as it advances through the media path. If the motion of the media is not sensed by the jam sensor (70), then a signal is displayed to the operator indicating a jam in the media path (24). When the user is finished using the selected media supply cassette (16), and wishes to use the media supply cassette normally mounted in bracket (8), the media in the path is cut on an output side beyond the drive roller assembly (30). The drive roller motor (39) is operated in reverse and simultaneously a supply cassette rewind motor (72) is turned on. The media is extracted from the media path (24) back up feed path (20), and rewound onto the supply core (74) of the supply cassette (16). The rewind motor (72) is attached to the supply core (74) by conventional gearing (not shown). A leading edge of the media is left extending out from the supply cassette (16) past driven roller (34). This rewind procedure allows the media previously in the media path (24) to be used at a later time. Then the media path (24) is clear for media from the supply cassette normally mounted in bracket (8), to enter through the feed path (18). A media sensor (76) (Fig. 1) senses the presence or lack of presence of media in the media path (24), and following the rewind procedure, displays a signal to the operator indicating that a new media selection or input command may be made. The process is then repeated. Selection of the supply cassette normally mounted in bracket (8), moves the drive roller (36) into driving contact with driven roller (32). This occurs by the action of the eccentric shaft (46) urging the bracket (50) to the left as viewed in Fig. 1 and pivoting the drive roller (36) in a counterclockwise direction around the pivot point (58). Overdrive of the eccentric shaft (46) causes compression of the spring (56) on the left side of aperture (48). A flag (80) mounted on bracket (38) breaks a beam of light within a photo interrupter (82) when the drive roller has reached the proper position against driven roller (32) and the gear motor (45) is switched off. While this invention has been described in terms of a preferred embodiment, those skilled in the art will appreciate that various modifications, substitutions, omissions and changes may be made. Accordingly, it is intended that the scope of the present invention be limited solely by the scope of the following claims.

Claims: A method for selecting media from one of two media supply cassettes to feed the media into a media path, comprising the subsequent steps of: a. inputting a command to designate one of the two media supply cassettes as a selected supply cassette (16); b. automatically positioning a movable drive roller (36) to be in driving contact with one of two driven rollers (34; 32) respectively mounted adjacent the two media supply cassettes, the drive roller (36) and the driven rollers (34; 32) being arranged in parallel, said positioning of the drive roller (36) taking place in response to said inputting of the command, to pinch between the drive roller and the one of the two driven rollers adjacent to the selected supply cassette a leading edge of media extending out from the selected supply cassette (16) into a feed path (20; 18) of the selected supply cassette; and, c. driving the drive roller (36), thereby rotating said one of two driven rollers (34; 32) and feeding the media out from the selected supply cassette (16) through the feed path (20) and into the media path (24). The method according to claim 1 further comprising the additional subsequent steps of: d. cutting the media on an output side of the media path, beyond the drive roller (36); and, e. driving the drive roller (36) in reverse and simultaneously rewinding the selected supply cassette, thereby returning the length of media in the media path (24) to the selected supply cassette (16) such that the leading edge (44) of the media extends into the feed path (20) past the driven roller (34), only. The method according to claim 1 wherein automatically positioning the drive roller includes the steps of: b1. rotating an eccentric shaft (46); b2. translating rotational movement of the eccentric shaft (46) into pivotal motion of the drive roller (36); and, b3. generating firm contact between the drive roller (36) and the driven roller (34; 32) by further rotating the eccentric shaft (46) to effectively pinch the leading edge of media. The method according to claim 3 wherein in step b3 the further rotation of the eccentric shaft (46) causes a spring (56) to be compressed, the spring force in turn generating a pressing force acting between the drive roller (36) and the driven roller (34; 32). An apparatus for selecting one of two media supply cassettes to feed media into a media path, comprising: a. input means for inputting a command designating a selected supply cassette; b. positioning means for automatically positioning a movable drive roller (36) to be in driving contact with one of two driven rollers (34; 32) respectively mounted adjacent the two media supply cassettes (16), the drive roller (36) and the driven rollers (34; 32) being arranged in parallel, said positioning of the drive roller (36) taking place in response to said inputting of the command, to pinch between the drive roller (36) and the one of the two driven rollers (34; 32) adjacent to the selected supply cassette (16) a leading edge of media extending out from the selected supply cassette (16) into a feed path (20) of the selected supply cassette; and, c. driving means (39, 40, 41) for driving the drive roller (36), thereby rotating said one of two driven rollers (34; 32) and feeding the media out from the selected supply cassette (16) through the feed path (20) and into the media path (24). The apparatus according to claim 5 further comprising: d. cutting means for cutting the media on an output side of the media path beyond the drive roller (36); e. rewind means (72, 74) for rewinding the selected supply cassette thereby returning the length of media in the media path (24) to the selected supply cassette (16) such that the media extends out from the selected supply cassette into the feed path (20) past the driven roller (34), only. The apparatus according to claim 6 wherein said rewind means (72, 74) includes a rewind gear (74) mounted on the selected supply cassette (16) and a rewind motor (72) in driving contact with said rewind gear. The apparatus according to any of claims 5, 6 or 7 wherein said positioning means includes: b1. rotating means (45) for rotating an eccentric shaft (46); b2. translating means (38, 48, 50) for translating rotational movement of the eccentric shaft (46) into pivotal motion of the drive roller (36); and, b3. pressure generating means (45, 54, 56) for generating firm contact between the drive roller (36) and the driven roller (34; 32) acting upon further rotation of the eccentric shaft (46) to effectively pinch the leading edge of media. The apparatus according to claim 8 wherein the pressure generating means comprises a spring (56) which is compressed when the eccentric shaft (46) is further rotated, the spring being positioned in a manner that the spring force is translated into a pressing force acting between the drive roller (36) and the driven roller (34; 32). An apparatus for selecting one of two media supply cassettes to feed media into a media path, comprising: a. a housing (14); b. a first media path (18) and a second media path (20); c. a first driven roller (32) and a second driven roller (34) mounted for rotation within said housing (14), adjacent to said first media path (18) and said second media path (20), respectively; d. a drive roller (36) movably mounted to said housing (14) between said first driven roller (32) and said second driven roller (20) such that said first media path (18) is between said first driven roller (32) and said drive roller (36), and said second media path (20) is between said second driven roller (34) and said drive roller (36), said drive roller (36) being movable between two positions such that in a first position said drive roller (36) is in rolling contact only with said first driven roller (32) and in a second position said drive roller (36) is in rolling contact only with said second driven roller (34); and, e. positioning means (45, 46) for positioning said drive roller (36) between said first position and said second position. The apparatus according to claim 10, further comprising: a. a drive gear (41) fixed to said drive roller (36) so as to be movable therewith and so as to rotationally drive said drive roller (36); b. a first driven gear (42) fixed to said first driven roller (32), said first driven gear (42) being fully engaged with said drive gear (41) when said drive roller (36) is in said first position and at least partially engaged with said drive gear (41) when said drive roller (36) is in said second position; and, c. a second driven gear (43) fixed to said second driven roller (34), said second driven gear (43) being fully engaged with said drive gear (41) when said drive roller (36) is in said second position and at least partially engaged with said drive gear (41) when said drive roller (36) is in said first position.

Inventors: KOZLOWSKY EDWARD P, LYONS JOSEPH R, KOZLOWSKY, EDWARD P., LYONS, JOSEPH R.
Applicants: AGFA CORP, AGFA CORPORATION
Application year: 1994
Main classification: H04N1
IPC codes: H04N1